• Journal of environmental and Sanitary engineering
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• v.7 no.2
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• pp.111-128
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• 1992

According to the increase of population and industrialization, the quality of our drinking water are becoming worse by the contamination of resources, production of THM and other halogenated hydrocarbons during the purifying process, the problem of corroded water supplying pipeline, and the water reservoir tanks, Many people choose groundwater to drink instead of city tap water, but sometimes we get report about groundwater contamination by wastes, swage, septic tank, etc. It is reported that in U. S. over 20% of population are drinking groundwater, but U. S EPA reported the groundwater contamination by pesticides, herbicides, fungicides, fertilizer, and various chemical substances. Craun, et at announced the groundwater contamination by bacteria which are related with poor installation of septic tank. Johnson and Kross mentioned aboutmethemoglobinemia by NO3-N originated from human and animal feces, organic chemicals, and fertilizer, and as the results the infant mortality could be risen. Some scientist also reported the high concentration of metals in groundwaters and some cation and anions, and volatile organic compou nds. Authors investigated 80 groundwaters in urban, agricultural, and industrial area during last 3 month(June - August) to check any drinking water quality parameters are exceeding the standards. The results were as follow. 1, The average value of ammonia nitrate were within the standard, but 11.76% of urban area were exceeded the 10 rpm standard, in agricultural area 42.3175 were exceeded, and in industrial area 20.2% were exceeded the drinking water standard of 10 ppm. the highest concentration was 29.37 ppd in industrial area. 2. The mean value of metals is not exceeded the standard, but there were some groundwater whose Mn value was 0.424 ppm(standard is 0,3 ppm) in urban area, 0.737 rpm in agricultural area, and 5.188 ppm in industrial area. The highest Zn value was 1.221 ppm (standard is 1.0 ppm)was found in industrial area. 3. The percentage of contamination by general bacteria was 8.82% in urban area, 15.38% in agricultural area, and 15.00% in industrial area. Escherichia coil group was also contaminated by 35.29% in urban area, 30.76% in agricultural area, and 30.00% in industrial area. 4, The pH value was within the standard which means there was no influence by acid or alkali chemicals, nor acid rain Through the above results, all the groundwater should be tested to check the safety for drinking water and should make some alternative methods suitable for drink.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.291-295
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• 2002

We measured the concentrations of heavy metals and VOCs in groundwaters (N=38) in Seoul. The comparison of our data with U.S. Environmental Protection Agency's Maximum Contaminant Levels for Drinking Water and with the Korean Drinking Water Standards shows that most of the metals except for Fe and Mn do not exceed the levels. However, the concentrations of most heavy metals (esp., Zn, Cu, Cr, Ni) tend to increase in residential and industrialized areas. The examination of the metal speciation using Anodic Stripping Voltammetry (ASV) and TOC analyzer Indicates that large amounts of Zn occur as labile metal fraction, whereas Cu occurs as non- labile forms at many sites, possibly due to its tendency to be adsorbed onto inorganic colloidal particles to form electroinactive species in groundwater. The most frequently existed VOCs in Seoul groundwaters are trichloroethylene and tetrachloroethylene, especially in agricultural, industrial, and high traffic areas.

• Journal of Korea Water Resources Association
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• v.55 no.12
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• pp.1031-1039
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• 2022

As one of the hydrological factors closely related to landslides, precipitation indirectly affects slope stability by generating external forces. Groundwater level fluctuations have attracted more attention lately as factors that directly affect slope stability have become more prominent. Therefore, this study attempted to analyze the relationship between variables through changes in precipitation, groundwater levels, and land displacement. A time series-based analysis was conducted using satellite-based precipitation and point-based groundwater levels in conjunction with the PSInSAR technique to simulate land displacement in urban and mountainous areas. There was a sharp rise in groundwater levels in both urban and mountain areas during heavy rainfall, and a continuous decrease in urban areas when rainfall was low. 6 mm of displacements was observed in the mountainous area as a results of soil outflow from the topsoil layer, which was accompanied by an increased groundwater level. Meanwhile, different results were found in urban area. In response to the rise in groundwater level, the land displacement increases due to the expansion of soil skeletons, while the decrease seems to be attributed to anthropogenic influences. Overall, there was no consistent relationship between groundwater levels and land displacement, which appears to be caused by factors other than hydrological factors. Additional consideration of environmental factors could contribute to a deeper understanding of the relationship between the two factors.

• Journal of Korean Society on Water Environment
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• v.22 no.5
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• pp.815-823
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• 2006

The hydrologic cycle in urban catchment has been changed due to the expansion of impervious area by rapid urban development. In this study, the SWMM 5 (Storm Water Management Model 5) model was used to simulate the hydrologic cycle of the Dorimcheon catchment which suffers from the distorted hydrologic cycle as a typical urban catchment. This study compare continuous simulation of urban runoff combining the channel and sewer system with that of channel only in the Dorimcheon catchment. Continuous simulations of urban runoff were performed for the upstream basin of Dorim bridge. The urban impervious regions were processed by the land use analysis from LANDSAT_TM images. It was performed from 1975 to 2000 for every five years. Surface, groundwater and wastewater runoffs were additionally included in the simulations one at a time. Such simulations made it possible to evaluate those components quantitatively. The result of continuous simulation of urban runoff combining the channel and sewer system is that peak flow and recession are well simulated. The analysis results of urbanization effect on runoff are as follows: the surface runoff in 2000 increases to 64% of the whole precipitation whereas the surface runoff in 1975 amounts to 46% of the precipitation; the groundwater runoff in 2000 amounts to 6% and shows 8% decrease during the period from 1975 to 2000.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.10a
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• pp.81-82
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• 2005

• Proceedings of the KSEEG Conference
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• 2005.04a
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• pp.131-135
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• 2005

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1999.04a
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• pp.51-52
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• 1999

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.471-474
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• 2003

There has been a steady increase in geoenvironmental engineering projects where geotechnical engineering has been combined with environmental concerns. This study investigate on contaminant around unsanitary landfill situated in urban area and was carried out to evaluate the geoenvironmental characteristics of this site. As a result of this study, groundwater and soil around this landfill site was evaluated for analysis of physical and chemical properties.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.430-433
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• 2003

Nitrogen pollution in urban and rural groundwater is a common problem and poses a major threat to drinking water supplies based on groundwater. In this work, the kinetics of nitrification-denitrification coupled reactions are modeled and new reaction modules for the RT3D code describing the fate and transport of nitrogen species, dissolved oxygen, dissolved organic carbon, and biomass are developed and tested. The proposed nitrogen transformations and transport model showed very good match with the results of other public codes.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.129-135
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• 2000

Four types of land use were selected for sampling and study with different characteristics of heavy metal contamination during the period from August 1998 to June 2000. A series of studies have been carried out concerning the physicochemical characteristics of the sediments settling down in a gully pot to evaluate the contamination of Pb, Zn, Cd, Co, Cr and Cu. An examination of six elements indicated that Zn, Cu and Pb were the heavy metals severely impacted by anthropogenic input in Seoul. An assessment of 60 volatile organic compounds (VOCs) in urban runoff and ground water was conducted based on samples collected from 31 sites and 12 wells, respectively, in Seoul City. The higher levels of alkyl benzenes in urban runoff indicated that Seoul areas were mainly contaminated through traffic sources.